rkvm

rkvm is a tool for sharing keyboard and mouse across multiple Linux machines. It is based on a client/server architecture, where server is the machine controlling mouse and keyboard and relays events (mouse move, key presses, ...) to clients.

Switching between different clients is done by a configurable keyboard shortcut.

Features

• TLS encrypted by default, backed by rustls
• Display server agnostic (in fact, it doesn't require a display server at all)
• Low overhead

Requirements

• The uinput Linux kernel module, enabled by default in most distros. You can confirm that it's enabled in your distro by checking that /dev/uinput exists.
• libevdev development files (sudo apt install libevdev-dev on Debian/Ubuntu)
• Clang/LLVM (sudo apt install clang on Debian/Ubuntu)

Manual installation

If you can, it is strongly recommended to use the AUR package to install rkvm.
Note that the master branch can contain untested and breaking changes - for regular use, it is recommended to pick the latest release instead.

$ cargo build --release
# cp target/release/rkvm-client /usr/bin/
# cp target/release/rkvm-server /usr/bin/
# cp target/release/rkvm-certificate-gen /usr/bin/ # Optional
# cp systemd/rkvm-client.service /usr/lib/systemd/system/
# cp systemd/rkvm-server.service /usr/lib/systemd/system/

Configuration

After installation:

• Generate a certificate and private key using the rkvm-certificate-gen tool or provide your own from other sources.

• For server, place both the certificate and private key in /etc/rkvm/certificate.pem and /etc/rkvm/key.pem respectively.

• For client, place the certificate to /etc/rkvm/certificate.pem.

• Create a config if you haven't done so already.
  Server:

  # cp /usr/share/rkvm/examples/server.toml /etc/rkvm/server.toml
  

  Client:

  # cp /usr/share/rkvm/examples/client.toml /etc/rkvm/client.toml
  

  Do not edit the example configs, they will be overwritten by your package manager.

• Change the password and optionally reconfigure the network listen address and key bindings for switching clients

• Since rkvm-server grabs all input, i's a good idea to do a test run first to make sure you won't end up being unable to user your keyboard and/or mouse because your display server is not properly configured to receive input from rkvm.

  Run the following command to start rkvm-server for 15 seconds to test that your keyboard, mouse, etc. works properly:

  # rkvm-server /etc/rkvm/server.toml --shutdown-after 15
  

• Enable and start the systemd service.
  Server:

  # systemctl enable rkvm-server
  # systemctl start rkvm-server
  

  Client:

  # systemctl enable rkvm-client
  # systemctl start rkvm-client
  

Why rkvm and not Barrier/Synergy?

The author of this program had a lot of problems with said programs, namely his keyboard layout (Czech) not being supported properly, which stems from the fact that the programs send characters which it then attempts to translate back into keycodes. rkvm takes a different approach to solving this problem and doesn't assume anything about your keyboard layout -- it sends raw keycodes only.

Additionally, rkvm doesn't even know or care about X, Wayland or any display server that might be in use, because it uses the uinput API with libevdev to read and generate input events.

Regardless, if you want a working and stable solution for crossplatform keyboard and mouse sharing, you should probably use either of the above mentioned programs for the time being.

Limitations

• Linux only

Project structure

• rkvm-server - server application code
• rkvm-client - client application code
• rkvm-input - handles reading from and writing to input devices
• rkvm-net - network protocol encoding and decoding
• rkvm-certificate-gen - certificate generation tool

Bincode is used for encoding of messages on the network and Tokio as an asynchronous runtime.

Contributions

All contributions, that includes both PRs and issues, are very welcome.

Donations

If you find rkvm useful, you can donate to the original author and maintainer using Ko-fi.

License

MIT